Turndown perforated plate type apparatus equipped with hot fluid pipes for drying pulverant materials

ABSTRACT

A TURNDOWN PERFORATED PLATE TYPE APPARATUS EQUIPPED WITH HOT FLUID PIPES FOR DRYING PULVERANT MATERIALS, COMPRISING A BOILER CASING HAVING COMBINATIONS OF TWIN BLADE TYPE TURNDOWN PERFORATED PLATE MEANS AND HOT PIPE MEANS FOR SUPPLYING HOT AIR FROM BELOW THE PERFORATED PLATE MEANS TO INTRODUCE THE HEATED MEDIUM THROUGH THE SWIRLS OF FLUIDIZED PULVERANT MATERIAL, EACH OF SAID PERFORATED PLATE MEANS CONSISTING OF A PARTITION PLATE PROVIDED DIAMETRALLY OF THE BOILER CASING, A PAIR OF ROTATING SHAFTS LOCATED PARALLEL TO SAID PARTITION PLATE AND ROTATABLY SUPPORTED BY THE BOILER CASING, AND A PAIR OF SEMICIRCULAR FRAMES SUPPORTING SEMICURCULAR PERFORATED PLATES THEREIN AND WHICH ARE SECURED AT THE STRAIGHT ENDS TO THE ROTATING SHAFTS, SAID COMBINATIONS BEING ARRANGED IN A VERTICAL SERIES WITHIN SAID BOILER CASING.

March 16, 1971 JIYUICHI NARA 3,570,134

TURNDOWN PERFORATED PLATE TYPE APPARATUS EQUIPPED WITH HOT FLUID PIPES FOR DRYING PULVERANT MATERIALS Filed Sent. 24, 1969 5 Sheets-Sheet 1 BY A 3 Sheets-Sheet 2 Man}! 1971 JIYUICHI NARA TuRNgggNFiERFokATfiD PLATE TYPE -APPARATUS EQUIPPED WITH UID PIPES FOR DRYI G Filed Sept. 24' 1969 r N PULVERANT MATERIALS M QW INVENTOR.

ar f 1971 JIYUICHI NARA ,57

TURNDOWN PERFORATED PLATE TYPE APPARATUS EQUIPPED WITH HOT FLUID PIPES FOR DRYING PULVERANT MATERIALS Filed Sent. 24, 1969 3 Sheets-Sheet 3 L'L i u 7 4.

a :6 l O 1 INVENTOR.

United States Patent Oflice 3,570,134 TURNDOWN PERFORATED PLATE TYPE AP- PARATUS EQUIPPED WITH HOT FLUID PIPES FOR DRYING PULVERAN T MATERIALS .Iiyuichi Nara 2-7-8 Higashi-ooi, Shinagawa-ku, Tokyo, Japan Filed Sept. 24, 1969, Ser. No. 860,642 Int. Cl. F2611 17/14 U.S. Cl. 34-57 1 Claim ABSTRACT OF THE DISCLOSURE A turndown perforated plate type apparatus equipped with hot fluid pipes for drying pulverant mtaerials, comprising a boiler casing having combinations of twin blade type turndown perforated plate means and hot pipe means for supplying hot air from below the perforated plate means to introduce the heated medium through the swirls of fluidized pulverant material, each of said perforated plate means consisting of a partition plate provided diametrally of the boiler casing, a pair of rotating shafts located parallel to said partition plate and rotatably supported by the boiler casing, and a pair of semicircular frames supporting semicircular perforated plates therein and which are secured at the straight ends to the rotating shafts, said combinations being arranged in a vertical series within said boiler casing.

BACKGROUND OF THE INVENTION This invention relates to an apparatus of turndown perforated plate type for drying pulverant material, equipped with hot fluid pipes above the upper side of perforated plates.

A prior art apparatus for drying damp pulverant material while fluidizing the same over a perforated plate, wherein the same plate is turned down to drop the dried material therefrom. The known device comprises a circular perforated plate adapted to turn down around a single shaft provided diametrally of the casing. The system is disadvantageous because, in order that the perforated plate may turn at right angles to the horizontal plane, there must be provided above the horizontal position of the plate a space corresponding to the radius of the plate and keep it free of other component units. This means that a large space should be provided for the ascending half of the turning plate. In addition, as the perforated plate is turned around the center shaft, the pulverant material on the perforated plate drops from the one half part of the plate that is turned down, all onto the corresponding half of the perforated plate or the like installed underneath the first perforated plate. Thus, the underlying perforated plate or the like receives an irregular supply of pulverant material, concentrated on one half of the plate, and therefore it takes much time with a disadvantage before the mass of particles dropped onto the perforated plate or the like is leveled naturally to a layer of generally adequate thickness. On the other hand, when a pulverant material on the perforated plate is to be dried while being fluidized with hot air supplied from below the plate, the provision of hot pipes in the swirls of fluidized pulverant material is indispensable for the supply of latent heat of evaporation of the volatile matter in the pulverant material to enhance thereby the drying effect of the hot air. For the reason above stated, it has heretofore been impossible wtih the conventional apparatus using a circular perforated plate to provide hot tubes in the fluidized material.

Patented Mar. 16, 1971 SUMMARY OF THE INVENTION The present invention has for its object to provide a turndown perforated plate type apparatus for drying pulverant materials which eliminates the disadvantages of the conventional circular turndown perforated plate and makes most of the advantageous effect of hot tubes for the enhancement of drying efficiency.

The present invention has been perfected to realize the above object. It thus pertains to a turndown perforated plate type apparatus equipped with hot fluid pipes for drying pulverant materials, comprising a boiler casing having an inlet port for the supply of damp pulverant material and exhaust port for humidified gas on the upper part thereof, a discharge port for dried pulverant material on the lower part thereof and an inlet port for the supply of drying gas below perforated plates, and combinations of twin blade type turndown perforated plate means and hot pipe means for supplying hot air from below the perforated plate means to introduce the heated medium through the swirls of fluidized pulverant material, each of said perforated plate means consisting of a partition plate provided diametrally of the :boiler casing, a pair of rotating shafts located parallel to said partition plate and rotatably supported by the boiler casing, and a pair of semicircular frames supporting semicircular perforated plates therein and which are secured at the straight ends to the rotating shafts, so that the perforated plates can swing downward from the boiler casing by an angle between the horizontal position and the position perpendicular thereto, said combinations being arranged in a vertical series within said boiler casing.

The present invention will now be explained by reference to the accompanying drawings showing an embodiment of turndown perforated plate type apparatus equipped with hot fluid pipes for drying pulverant materials according to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial side view, in vertical section taken along the line AA of FIG. 2, illustrating the essential part of the drying apparatus embodying the invention;

FIG. 2 is a plan view taken along the line BB of FIG. 1 with the upper part cut away;

FIG. 3 is a vertical sectional view taken along the line CC of FIG. 4, showing the perforated plate assembly of the drying apparatus of the invention;

FIG. 4 is a plan view of the structure shown in FIG. 3; and

FIG. 5 is a schematic view illustrating the embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown generally in FIG. 5, the present invention is concerned With a pulverant material drying apparatus of turndown perforated plate type equipped with hot fluid pipes, comprising a boiler casing 5 having an inlet port 1 for the supply of damp pulverant material and an exhaust port 2 for humidified gas on the upper part thereof, a discharge port 3 for dried pulverant material on the lower part thereof and an inlet port 4 for the supply of drying gas below perforated plates, and combinations of twin blade type turndown perforated plate means (FIGS. 1, 2 and 5) and hot pipe means 10 for supplying hot air from below the perforated plate means to introduce the heated medium through the swirls of fluidized pulverant material, each of said perforated plate means consisting of a partition plate -6 provided diametrally of the boiler casing 5 (FIGS. 1 to 4), a pair of rotating shafts 7, 7 located parallel to said partition plate 6 and rotatably supported by the boiler casing 5, and a pair of semicircular frames 8, 8 supporting semicircular perforated plates 9, 9 therein and which are secured at the straight ends to the rotating shafts 7, 7, so that the perforated plates 9, 9 can swing downward from the boiler casing by an angle between the horizontal position and the position perpendicular thereto, said combinations being arranged in a vertical series within said boiler casing. Reference numeral 11 indicates an inlet and numeral 12 indicates outlet for the heating medium respectively.

In the pulverant material drying apparatus according to the present invention, the perforated plates 9 fitted in the pair of semicircular frames 8 on both sides of the partition plate 6 are fixedly secured to the rotating shafts 7 and each plate 9 can be turned down out of contact with the casing wall of the boiler 5 to the point at an angle of 90 degrees with respect to the horizontal position. Accordingly, the space above each perforated plate in the horizontal position has only to be equivalent to the distance between the associated shaft 7 and partition plate 6, and the hot fluid pipes 10 are disposed immediately outside the above space. This arrangement is outstandingly advantageous in that the hot fluid pipes 10 are provided in the swirls of the fluidized pulverant material and can be sufficiently replenished with heat through the medium to avoid the drop of hot air temperature and hence the weakening of the drying action due to the latent heat of evaporation of the volatile matter in the pulverant material. Furthermore, when a plurality of the twin blade turndown perforated plate assemblies are arranged in a vertical series as shown in FIG. 5, the mass of pulverant material drops from the upper perforated plates in two lots onto the lower perforated plates, thus requiring a very short period of time for the leveling of the pulverant material layer on the lower perforated plate assembly, as compared with the period of time usually required by a series of conven tional circular turndown perforated plates.

With 'the functions above explained, the apparatus according to the present invention can efficiently perform the drying of pulverant materials with practical advantages.

What is claimed is:

1. A turndown perforated plate type apparatus equipped with hot fluid pipes for drying pulverant materials, comprising a boiler casing having an inlet port for the supply of damp pulverant material and an exhaust port for humidified gas on the upper part thereof, a discharge port for dried pulverant material on the lower part thereof and an inlet port for the supply of drying gas below perforated plates, and combinations of twin blade type turndown perforated plate means and hot pipe means for supplying hot air from below the perforated plate means to introduce the heated medium through the swirls of fluidized pulverant material, each of said perforated plate means consisting of a partition plate provided diametrally of the boiler casing, a pair of rotating shafts located parallel to said partition plate and rotatably supported by the boiler casing, and a pair of semicircular frames supporting semicircular perforated plates therein and which are secured at the straight ends to the rotating shafts, so that the perforated plates can swing downward from the boiler casing by an angle betweenthe horizontal position and the position perpendicular thereto, said combinations being arranged in a vertical series within said boiler casing.

References Cited UNITED STATES PATENTS 3,230,635 1/1966 Dietert 3457 3,263,346 8/1966 Validenhoeck 3410 EDWARD G. FAVORS, Primary Examiner 

